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Extensive gingival necrosis and sequestration of the alveolar bone caused by methimazole-induced neutropenia and three-year follow-up

  • Kim, Eun-Cheol;Park, Joon Bong;Hong, Ji-Youn;Kang, Kyung Lhi
    • Journal of Periodontal and Implant Science
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    • v.45 no.2
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    • pp.76-80
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    • 2015
  • Purpose: Methimazole is an anti-thyroid drug that can cause life-threatening neutropenia in rare situations. The aim of this case report is to describe a set of oral complications associated with methimazole-induced neutropenia and the healing of the gingiva after proper treatment. Methods: A 31-year-old female patient hospitalized for systemic symptoms of sore throat and fever and showing extensive gingival necrosis with pain was referred to the Department of Periodontics from the Department of Endocrinology. Methimazole-induced neutropenia was diagnosed based on blood test results and her medical history. Methimazole was discontinued and a range of treatments was administered, including the injection of granulocyte colony stimulating factor. Results: After systemic treatment, the gingiva began to heal as the neutrophil count increased. Approximately one year later, the gingiva had returned to a normal appearance. Twenty-one months after treatment, sequestra of the alveolar bone that had broken through the gingiva were removed. Periodic supportive periodontal treatment has been continued uneventfully. Conclusions: The oral manifestations of gingival necrosis and ulcerations, in combination with systemic symptoms such as fever and sore throat, are the critical signs presented in the early stages of drug-induced neutropenia. Therefore, dentists need to be aware of these oral complications in order to make an accurate diagnosis and to ensure that prompt medical intervention is provided.

COMPENSATION EFFECT OF EXPOSURE TIME INCREASE TO DECREASED LIGHT INTENSITY OF VISIBLE-LIGHT CURING UNIT (가시광선 중합기의 조사강도 감소에 대한 조사시간 증가의 보상효과)

  • Yoon, Tae-Won;Lee, Chang-Seop;Lee, Sang-Ho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.24 no.1
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    • pp.325-336
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    • 1997
  • The purpose of this study was to evaluate the compensation effect of exposure duration increase to decreased light intensity of visible-light curing unit. The specimen with 2mm thickness was made of Restorative $Z-100^{TM}$ (A2 shade, 3M Dental Products, U.S.A.) and cured with $Optilux^{TM}$ (Demetron Research Co. U.S.A.). The light intensity was controlled to 420 $mW/cm^2$, 540 $mW/cm^2$, 630 $mW/cm^2$ and curing time, also, controlled to 40, 60, 80 seconds. Cured specimen was stored in a light-proof container for 24 hours to post-irradation was completed. Microhardness of top and bottom surface of specimen were measured to evaluate the depth of cure. The obtained results were as follows: 1. The microhardness of top and bottom surface of the composite resin specimen was increased significantly as light intensity and exposure time was increased (P<0.01). 2. Light intensity was more correlated with bottom microhardness(${\gamma}{\geq}$0.438) than top microhardness(${\gamma}{\geq}$0.213), and exposure time was more correlated with top microhardness (${\gamma}{\geq}$0.424) than bottom microhardness(${\gamma}{\geq}$0.335). 3. The regressive equation was obtained in this study as follows : $H=0.07{\times}D+0.012{\times}I+76$ (H : Microhardness(KHN), D : Exposure time, I : Light intensity)

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A Study on Relationship between Halitosis Causing Factors and Components (구취 유발요인과 성분 간의 관계 연구)

  • Ji, Min-Gyeong
    • The Journal of the Korea institute of electronic communication sciences
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    • v.8 no.12
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    • pp.1971-1978
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    • 2013
  • The aim was to be utilized as basic data in arranging efficient plan for removing halitosis by surveying correlation with halitosis components by each factor after measuring halitosis and analyzing components by subject of adults on halitosis. It targeted totally 160 people by 80 outpatients of 1 dental hospital, respectively, where is located in Daejeon and Chungnam, for 12 months from February 1, 2011 to January 30, 2012. As a result of analysis, in the halitosis measurement value of Oral chroma, it was shown to be 9.4% in case of being more than 112ppb in the measurement value of hydrogen sulfide, 20.6% in case of being more than 26ppb in the measurement value of methyl mercaptan, and 44.0% in case of being more than 8ppb in the measurement value of dimethyl sulfide, which was indicated to be the highest value among three components. Only the methyl mercaptan component and the dimethyl sulfide component, which were measured with oral chroma, stood at 0.578, thereby having been shown to have high positive correlation. Accordingly, a multilateral research is considered to be likely necessity as for diverse components of causing halitosis.

Distortion of Magnetic Resonance Imaging for Different Types of Orthodontic Material (치과 교정 물질에 따른 자기공명영상의 왜곡)

  • Song, Hyun-Og;Lim, Cheong-Hwan;Lee, Sang-Ho;Yang, Oh-Nam;Baek, Chang-Moo;Jung, Hong-Ryang
    • Journal of Digital Convergence
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    • v.12 no.2
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    • pp.439-446
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    • 2014
  • To evaluate the effects of an artifact by metal material for orthodontics in Magnetic Resonance Image (MRI) examination, wires and brackets used in orthodontics were selected and compared. Using a head coil, a $T_2$-weighted image, $T_1$-weighted image and FLAIR image were obtained. With obtained images, the sizes of the artifacts were measured and compared using Image J Program. In the research, the material with the biggest artifact in the wires and brackets for orthodontics was stainless steel wire. In the future, selecting and developing metal for correction should be considered also in other fields along with the purpose of orthodontics.

An assessment of the taxonomic reliability of DNA barcode sequences in publicly available databases

  • Jin, Soyeong;Kim, Kwang Young;Kim, Min-Seok;Park, Chungoo
    • ALGAE
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    • v.35 no.3
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    • pp.293-301
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    • 2020
  • The applications of DNA barcoding have a wide range of uses, such as in taxonomic studies to help elucidate cryptic species and phylogenetic relationships and analyzing environmental samples for biodiversity monitoring and conservation assessments of species. After obtaining the DNA barcode sequences, sequence similarity-based homology analysis is commonly used. This means that the obtained barcode sequences are compared to the DNA barcode reference databases. This bioinformatic analysis necessarily implies that the overall quantity and quality of the reference databases must be stringently monitored to not have an adverse impact on the accuracy of species identification. With the development of next-generation sequencing techniques, a noticeably large number of DNA barcode sequences have been produced and are stored in online databases, but their degree of validity, accuracy, and reliability have not been extensively investigated. In this study, we investigated the extent to which the amount and types of erroneous barcode sequences were deposited in publicly accessible databases. Over 4.1 million sequences were investigated in three largescale DNA barcode databases (NCBI GenBank, Barcode of Life Data System [BOLD], and Protist Ribosomal Reference database [PR2]) for four major DNA barcodes (cytochrome c oxidase subunit 1 [COI], internal transcribed spacer [ITS], ribulose bisphosphate carboxylase large chain [rbcL], and 18S ribosomal RNA [18S rRNA]); approximately 2% of erroneous barcode sequences were found and their taxonomic distributions were uneven. Consequently, our present findings provide compelling evidence of data quality problems along with insufficient and unreliable annotation of taxonomic data in DNA barcode databases. Therefore, we suggest that if ambiguous taxa are presented during barcoding analysis, further validation with other DNA barcode loci or morphological characters should be mandated.

Effect of Rhizoma Gastrodiae on Cultured Spinal Motor Neurons Damaged by Oxygen Radicals (천마가 산소자유기로 손상된 생쥐의 배양 척수 운동신경세포에 미치는 영향)

  • Son IL Hong;Lee Jung Hun;kim Sang Su;Lee Kang Chang;Lee Young Mi;Hong Gi Youn;Moon Hyung Bae;Seo Eun A;Han Du Seok;Shin Min Kyo;Song Ho Joan;Park Seung Taeck
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.2
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    • pp.262-266
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    • 2002
  • In order to elucidate the mechanism of cytotoxic effect of oxygen radicals on cultured mouse spinal motor neurons, the neurotoxicity induced by hydrogen peroxide(H₂O₂) was evaluated by MTT assay. The neuroprotective effect of Rhizoma Gastrodiae(RG) against H₂O₂-mediated neurotoxicity was also examined in these cultures by SRB assay. The results were as follows : The value of lethal concentration 50(LC50) of H₂O₂ was estimated at a concentration of 30 uM in these cultures. Cell viability of cultured mouse spinal motor neurons was remarkably decreased by H₂O₂-induced neurotoxicity in a dose- and time-dependent manner. RG was remarkably effective in blocking the neurotoxicity induced by H₂O₂ at a concentration of 120 μM as determined by SRB assay. From above the results, it is suggested that H₂O₂ induce neurotoxicity, and the selective herbal extracted RG was very effective in blocking H₂O₂-mediated neurotoxicity on cultured mouse spinal motor neurons.

Production of Mn-Dependent Peroxidase from Bjerkandera fumosa and Its Enzyme Characterization

  • Jarosz-Wilkolazka, Anna;Luterek, Jolanta;Malarczyk, Elzbieta;Leonowicz, Andrzej;Cho, Hee-Yeon;Shin, Soo-Jeong;Cho, Nam-Seok
    • Journal of the Korean Wood Science and Technology
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    • v.35 no.2
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    • pp.85-95
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    • 2007
  • Manganese dependent peroxidase (MnP) is the most ubiquitous enzyme produced by white-rot fungi, MnP is known to be involved in lignin degradation, biobleaching and oxidation of hazardous organopollutants. Bjerkandera fumosa is a nitrogen-unregulated white-rot fungus, which produces high amounts of MnP in the excess of N-nutrients due to increased biomass yield. The objective of this study was to optimize the MnP production in N-sufficient cultures by varying different physiological factors such as Mn concentration, culture pH, and incubation temperature. The growth of fungus was optimal in pH 4.5 at $30^{\circ}C$, $N_2$-unregulated white-rot fungus produces high amounts of MnP in the excess N-nutrients. The fungus produced the highest level of MnP (up to $1000U/{\ell}$) with $0.25g/{\ell}$ asparagine and $1g/{\ell}$ $NH_4Cl$ as N source at 1.5 mM $MnCl_2$ concentration, pH value of 4.5 at $30^{\circ}C$. Purification of MnP revealed the existence of two isoforms: MnPl and MnP2. The molecular masses of the purified MnPl and MnP2 were in the same range of 42~45 kDa. These isoforms of B. fumosa strictly require Mn to oxidize phenolic substrates. Concerned to kinetic constants of B. fumosa MnPs, B. fumosa has similar Km value and Vmax compared to the other white-rot fungi.

A Study on the Effects of Maximum Voluntary Clenching on the Tooth Contact Points and Masticatory Muscle Activities in Patients with Temporomandibular Disorders (측두하악장애환자에 있어서 수의적 악물기시의 치아접촉점 및 저작근 활성에 관한 연구)

  • Jae-Kap Choi;Kyung-Soo Han
    • Journal of Oral Medicine and Pain
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    • v.15 no.1
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    • pp.105-115
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    • 1991
  • The purpose of the study was to evaluate the occlusal stability at the moment of dynamic occlusal tooth contact and to investigate the correlation between the occlusal stability and the masticatory muscle activities. It also evaluated the effect of short-term use of occlusal splints on the occlusal stability and the masticatory muscle activities in patients with temporomandibular disorders during maximum voluntary clenching by synchondronized with temporomandibular disorders during maximum voluntary clenching by synchronized use of the T-Scan system(Tekscan, Inc, USA) and K6-Diagnostic system(Myo-tronics Research, Inc, USA) The author measured its distance from retruded contact position(RCP) to intercuspal position(IP), average of contact intervals(ACI), total left-right statistics(TLR), average muscle activities of masseter and anterior temporal muscles during maximum voluntary clenching in 20 patients with temporomandibular disorders and 22 dental students as a control group. The data were compared between two groups and investigated for any correlations between the parameters. The results were as follows : 1. Both of the mean average of contact intervals and the mean absolute value of total left-right statistics during maximum voluntary clenching were increased in the patient group when compared with the control group. 2. Muscular disharmony of anterior temporal muscles of patient group is significantly greater than that of control group. However, muscular disharmony of masseter muscles of patient group is not significantly greater than that of control group. 3. There were significant correlations between muscular disharmony of anterior temporal muscles and average of contact intervals as well as total left-right statistics, and also between muscular disharmony of masseter muscles and total left-right statistics. 4. There were not any significant correlations between distance from RCP to IP and any other parameters. 5. There were a significant decrease in total left-right statistics and muscular disharmony of anterior temporal muscles during maximum voluntary clenching after a 1week use of occlusal splint in the patient group.

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Respiratory air Flow Transducer Based on air Turbulence (와류 현상을 이용하는 호흡기류센서)

  • Kim, Kyung-Ah;Lee, In-Kwang;Park, Jun-Oh;Lee, Su-Ok;Shin, Eun-Young;Kim, Yoon-Kee;Kim, Kyung-Chun;Cha, Eun-Jong
    • Journal of Biomedical Engineering Research
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    • v.30 no.5
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    • pp.393-400
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    • 2009
  • The present study developed a new technique with no physical object on the flow stream but enabling the air flow measurement and easily incorporated with the devices for cardiopulmonary resuscitation(CPR) procedure. A turbulence chamber was formed in the middle of the respiratory tube by locally enlarging the cross-sectional area where the flow related turbulence was generated inducing energy loss which was in turn converted into pressure difference. The turbulence chamber was simply an empty enlarged air space, thus no physical object existed on the flow stream, but still the flow rate could be evaluated. Computer simulation demonstrated stable turbulence formation big enough to measure. Experiment was followed on the proto-type transducer, the results of which were within ${\pm}5%$ error compared to the simulation data. Both inspiratory and expiratory flows were obtained with symmetric measurement characteristics. Quadratic curve fitting provided excellent calibration formula with a correlation coefficient>0.999(P<0.0001) and the mean relative error<1%. The present results can be usefully applied to accurately monitor the air flow rate during CPR.

Convergencial Neighborhood Environment Factors related to Walking Days - Centered on Age 20s to 30s Female in Metro Busan (걷기 일 수 관련 융복합적 근린환경 요인 - 부산광역시 20~30대 여성을 중심으로)

  • Kim, Myung-Gwan;Lee, Eun-Ju
    • Journal of the Korea Convergence Society
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    • v.8 no.8
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    • pp.299-305
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    • 2017
  • This study, using the data of the community health survey, chose 2,162 as research objects. To examine convergent neighborhood environmental factors related with walking days of women in their 20s and 30s in Busan city, this study conducted multiple regression analysis. The analysis found out that, the larger the picnic area is, the larger the number of sports facilities is, the larger the number of walking days of those women gets. It was also found out that students walk more often than those who do not work. The older women are, and the larger commercial areas are, the smaller the number of their walking days. Accordingly, it is necessary to design programs suitable to residents in different areas by collecting opinions of residents and testing priorities, necessity, and effectiveness.